如何在对象类型文档字段的属性上使用FieldValue.increment() [英] How to use FieldValue.increment() on the property of an object type document field

问题描述

Firestore的 FieldValue.increment(someValue)在其他字段上正常工作，但在地图上无法正常工作.

Firestore's FieldValue.increment(someValue) is working properly with other fields but not with map.

我正在尝试增加地图中属性的值.我有一个名为用户的文档.它具有地图 points:{id:123，total:100} .我想更新地图 points 中的 total 的值.

I am trying to increment the value of a property in a map. I have a document named user. It has a map points:{id:123, total:100}. I want to update the value of total in map points.

firestore.collection('users').doc('user').update({
    "name": "atul",
    "points": { "total": firestore.FieldValue.increment(50) }
})

而不是将 total 的值增加到150，而是将其值变成100.

Instead of incrementing the total value to 150, its value becomes 100.

推荐答案

您需要调出字段的完整路径以递增，而不是将其隐藏在对象中.字段的完整路径涉及使用.作为每个字段名称之间的分隔符:

You'll need to call out the full path of the field to increment, not bury it inside an object. The full path of the field involves using . as a separator between the names of each field:

firestore.doc(...).update({
    "points.total": firestore.FieldValue.increment(50)
})

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